Palatally impacted maxillary canines

In a special article entitled, "Impacted Maxillary Canines: A Review," Samir E. Bishara states: "The ectopic eruption and impaction of maxillary permanent canines is a frequently encountered clinical problem. The diagnosis and treatment of this problem usually requires the expertise and cooperation of the general practitioner, the paediatric dentist, the oral surgeon, and the periodontist, as well as the orthodontist." We will review the etiology, diagnosis and treatment of impacted maxillary canines. A technique will be outlined that allows a competent orthodontic clinician to singly, efficiently and reliably treat this common problem without reference to a myriad of specialists.     

Autogenous transplantation of impacted maxillary canines

The authors report on three patients who received four autogenous transplantations of impacted maxillary canines, relate the technique used, and discuss the advantages and disadvantages of this surgical procedure.     

Therapeutic strategies for impacted maxillary canines

A disturbance in the normal eruption pattern of one or both of the maxillary canines is found in 1% to 2% of the teenagers aged ten to thirteen years. Frequently, dentists refer these patients to orthodontists who, in turn, seek the assistance of an oral and maxillofacial surgeon to retrieve the impacted canine, either by exposure alone or by exposure and attachment of a bracket and ligature for orthodontic extrusion. A common request in this procedure is the extraction of the persistent upper deciduous canine and/or, in case of an Angle Class II molar relationship, extraction of the upper first premolar. It has been shown, however, that on average 15% of these exposed or ligated maxillary canines fail to erupt. Therefore, one should be reluctant to extract the deciduous canine or the permanent first premolar before it is clear that the impacted maxillary canine will indeed erupt after surgical exposure and/or placing of a bracket and ligature for orthodontic extrusion.     

Orthodontic treatment of palatally impacted maxillary canines

The aim of this study was to determine the feasibility of treating children with impacted maxillary canines by orthodontic treatment alone. The subjects were 28 children (mean age: 13.5 years, range 11.4-16.1 years) with between them 32 palatally impacted canines. The overlying primary canines were extracted between 0 and 42 months before the start of appliance treatment to open space in the arches for the impacted teeth. No other surgical procedures were carried out prior to the start of appliance treatment. Appliance treatment was deferred for at least six months if an impacted canine was the main reason for treatment, otherwise treatment was commenced according to the needs of the patient. In 94% of the cases, the severity of impaction lessened following extraction of the overlying primary canines and orthodontic treatment. The deepest impactions tended to occur in the oldest children. The majority (75%) of the canines emerged following orthodontic treatment to create space for them in the arch; the remainder were surgically exposed. Appliance treatment tended to take longer in children with the deepest impactions. It is concluded that fixed appliance treatment to create space for a palatally impacted canine is an effective management option for children with impacted maxillary canines.     

Orthodontic screws to extrude impacted maxillary canines

Objective

The impaction of maxillary canines is a frequently encountered clinical problem in orthodontic practice. Patients?? refusal to participate in long-term treatment or ankylosis of the impacted tooth result in various treatment difficulties. The aim of this study was to evaluate the possible role of mini-screws in the management of unerupted upper canines.

Patients and methods

In a series of 63 consecutive patients (27 males and 36 females, age range 14?C49?years, mean 22.7?years) with a total of 69 impacted maxillary canines, each impacted tooth was surgically exposed and an attachment bonded. An intraosseous screw with an endosseous body and intraoral neck section was inserted into the premolar?Cmolar interradicular space. Following soft tissue healing, orthodontic traction was initiated. After correction of the canine angulation, the mini-screw was removed and conventional orthodontic therapy completed.

Results

Of the 69?canines, 61 (88.41%) were extruded successfully. In the 7?cases that failed, skeletal anchorage spared both patients and clinicians the disappointment of customary long-term, unsuccessful orthodontic therapy. In one patient, the mini-screw was removed because of inflammation and pain before initiating orthodontic traction.

Conclusion

Our results demonstrate that mini-screw anchorage should be taken into consideration when extrusion of an impacted canine is planned.     

Interceptive approach to treatment of impacted maxillary canines

Impaction of maxillary canines can be prevented by early intervention in the mixed dentition phase after the correct diagnosis of malocclusion, reducing the complexity of the treatment. This article reports the case of a 10-year-old patient who possessed impacted maxillary canines and, after early extraction of primary canines, had reestablished favorable permanent successors' eruption axis. This 5-year radiographic follow-up study with panoramic radiography shows that this can be used in practice and that an effective control strategy ensures the accuracy in the inclination of the impacted canines. Treatment success is related to early diagnosis and strategic interceptive treatment choice.     

Prediction of the mesiodistal widths of maxillary permanent canines and premolars.

Multiple regression equations for prediction of the mesiodistal widths of the maxillary canines and premolars were developed for the right and left sides of the arches of males and females. The equations were developed from longitudinal data taken from ninety-two Caucasian children (forty-six boys and forty-six girls) who participated in the Iowa Growth Study. The multiple regression equations, when compared with three currently used methods of prediction, were the best predictors. The newly developed equations and other prediction methods currently in use were tested on longitudinal data taken from a sample of forty-three Caucasian orthodontic patients (sixteen males and twenty-seven females). Again, the multiple regression equations had the best performance.     

Periodontal status of orthodontically treated impacted maxillary canines.

Thirty-four unilateral palatal impacted maxillary canines were brought down by orthodontic means after a radical surgical exposure. The contralateral canines which had erupted unaided served as controls during the study. Measurements of the gingival pocket depths showed that the distal pocket on the treated teeth was significantly deeper than on the control teeth. The treated canines displayed significantly more loss of periodontal support on the buccal and palatal surfaces than did the untreated teeth. Radiographically, there was more alveolar bone loss on the mesial surfaces of the corrected than on the uncorrected canines, the mean distance being 2.06 and 1.51 millimeters, respectively. The age of the patients at the start of treatment did not seem to have any profound influence on the loss of attachment, but the individual variation was considerably greater in adults.     

上颌埋伏尖牙非手术助萌的正畸治疗

[摘要] 目的 探讨上颌埋伏尖牙非手术助萌正畸治疗的适应证及其临床效果。方法 选取10～15岁上颌埋伏尖牙患者20例,应用螺旋CT三维重建技术对其进行诊断,明确埋伏尖牙颌骨内位置、方向及牙根发育情况,选取适合病例12例通过正畸手段为埋伏尖牙开辟间隙,等待其自行萌出;8例采用外科翻瓣导萌术牵引导萌。结果 12例非手术助萌患者,正畸拓展足够间隙后经3～10个月上颌埋伏尖牙均自行萌出至正常位置,牙周附着健康;8例外科手术导萌患者,上颌埋伏尖牙正畸牵引到位后均有不同程度的牙周附着丧失,影响龈缘美观。结论采用螺旋CT三维重建技术可以立体直观的提供埋伏尖牙的信息,为临床医师明确诊断及制定治疗方案提供依据,减少手术适应证,使用非手术助萌的方法可使上颌埋伏尖牙自行萌出,避免手术创伤痛苦,萌出后牙周附着好。     

Long-term results of orthodontic treatment of impacted maxillary canines

A total of 61 children who had 83 maxillary canines impacted were followed up for a mean of 3.5 years (range 1.1-10.9 years) after treatment to evaluate the long-term results of the treatments. In most of the children, the impacted maxillary canines had been surgically exposed and treated with fixed orthodontic appliances. In 11 cases, lateral incisors had been extracted because of extensive root resorption. The esthetic results as well as functional and periodontal conditions were evaluated. Only four of the 61 children were not satisfied with the esthetic result, whereas orthodontists judged only 56% of the results as esthetically acceptable on clinical evaluation and 57% as esthetically acceptable on color slides. The periodontal conditions and the occlusal function on sides with previously impacted canines and on sides with normally erupted canines, on the whole, were similar. Exceptions were pocket depths of the left lateral incisors and left canines, but these variables were significantly different mainly because of one patient. In lateral movements of the mandible, however, significant differences in contact pattern were found between sides with normally erupted canines and sides with impacted canines. Canine rise occurred more often on working sides with normally erupted canines than with impacted canines.     

Orthodontic and periodontal outcomes of treated impacted maxillary canines

OBJECTIVE: To evaluate the influence of pretreatment radiographic features (alpha-angle, d-distance, and s-sector) on (1) the duration of active orthodontic traction and (2) the posttreatment periodontal status (pocket depth [PD] and keratinized tissue width [KT]) of impacted maxillary canines treated by a combined surgical (flap approach) and orthodontic (direct traction to the center of the ridge) treatment. MATERIAL AND METHODS: A study population of 168 patients (168 canines) was evaluated. Multiple regression analysis was used. RESULTS: Pretreatment radiographic variables were associated significantly with the duration of orthodontic traction. Age, sex, and site of impaction did not significantly affect the duration of traction. No significant differences in PD and KT were present at the end of surgical-orthodontic treatment with respect to any of the variables considered. The analysis of PD and KT variables after orthodontic treatment revealed a healthy periodontium. CONCLUSIONS: alpha-angle, d-distance, and s-sector are valid indicators for the duration of orthodontic traction. They are not prognostic indicators of final periodontal status of orthodontically-repositioned canines.     

Labially impacted maxillary canines causing severe root resorption of maxillary central incisors

This is a case report of a patient with bilateral labial impaction of maxillary canines causing pressure resorption on the lateral aspects of the maxillary central incisors. The orthodontic treatment plan included extraction of the impacted canines, positioned between the central and the lateral incisors. Six years after the orthodontic treatment, the affected central incisors remained asymptomatic.     

The prevalence of root resorption of maxillary incisors caused by impacted maxillary canines

Objectives

The aim of this study was to evaluate the prevalence of root resorption of maxillary incisors caused by impacted maxillary canines using low-dose dental computed tomography and to gain additional knowledge of the underlying aetiology and the progression of root resorption.

Materials and methods

A total of 440 patients (mean age, 24.7 years) with 557 impacted maxillary canines were examined regarding their location and the occurrence of root resorption of maxillary incisors.

Results

The frequency of root resorption was 2 % of central and 7.7 % of lateral maxillary incisors. The location of the 557 impacted canines within the dental arch was palatal in 67.5 %, buccal in 15.4 % and central in 17.1 %. No significant differences could be shown with respect to the width and the shape of the dental follicle of the impacted maxillary canines and the presence of root resorption of incisors. The presence of root resorption of central (p?<?0.0001) and lateral (p?<?0.023) maxillary incisors was significantly correlated with an existing contact relationship of the impacted maxillary canines.

Conclusions

Our investigation confirms the theory of prior reports comprising a much larger patient population, hypothesising that the dental follicle of impacted maxillary canines does not cause resorption of adjacent maxillary incisors per se.

Clinical relevance

Root resorption of maxillary incisors is correlated with effects of contact of the impacted maxillary canines, and these findings should be considered in treatment planning. Our findings are consistent with other reports and may develop new treatment approaches for the treatment of this sequela.     

Dental age of children and adolescents with impacted maxillary canines

INTRODUCTION: It is generally perceived that patients with palatally impacted canines experience a delay in dental development, while patients with buccally impacted canines do not. Nevertheless, there is little scientific data on the subject, and no data at all on Chinese populations. The objectives of this study were, thus, to determine whether patients with impacted canines would demonstrate delayed dental development. DESIGN: Retrospective radiographic study. SETTING: Dental hospital. METHODS: Our study enrolled southern Chinese children and adolescents with unilaterally impacted maxillary canines. A total of 281?panoramic radiographs were available to assess dental age. Demirjian's method was utilized to determine the dental age. RESULTS: The discrepancy between dental and chronologic ages was then calculated, revealing a mean difference of 0.4?years (±?0.2?years), indicating advanced dental development. The cumulative difference between dental age and chronologic age showed that 42.2% of the patients with a buccally impacted canine and 30% with a palatally impacted canine experienced a delay in dental development, or coincided with their chronologic age. CONCLUSION: Less than half of the patients with both buccally and palatally impacted canines showed delayed dental development. Their dental maturity was on average slightly but clinically insignificantly advanced.